Withholding periods are mandatory with all registered veterinary products used to treat food animals for internal and external parasites. These limits are set in Australia to ensure that meat and milk are safe to eat and to ensure that they do not exceed maximum residue limits (MRLs) for Australian and overseas markets. It is extremely important to ensure that cattle treatments are timed so that WHP can be observed and MRLs are not exceeded. There are three main withholding periods of concern in cattle:
Meat Withholding Period (Meat WHP) is the time from chemical application to when an animal can be slaughtered for domestic use.
Export Slaughter Interval (ESI) is the time from chemical application to when an animal can be slaughtered for export.
Milk Withholding Period (Milk WHP) is the time from chemical application to when milk can be taken from the animal for human consumption.
These withholding periods are stated on the labels of all registered veterinary products and on the APVMA website. Note that very occasionally in the case of older registered veterinary products there may not be an ESI listed on the label. In this case consult the APVMA website. When cattle are sold it is necessary for the owner to certify on the National Vendor Declaration (NVD) whether or not they are within the meat withholding period (WHP) or export slaughter interval (ESI) after treatment with veterinary drugs or chemicals.
Check with your processor to determine which withholding period to use as some processors export products such as offal so require ESI.